Court records showed Van Der Zwaan was charged with lying to investigators about work he did in 2012 in Ukraine. According to Bloomberg, Van Der Zwaan helped to prepare a report on the trial of former Ukrainian Prime Minister Yulia Tymoshenko on behalf of the Ukraine Ministry of Justice.

Van Der Zwaan lied to FBI investigators about his last contact with Rick Gates, who was indicted last year along with former Trump campaign manager Paul Manafort and charged in connection to consulting work they did in Ukraine, according to court records. Prosecutors said Van Der Zwaan also lied about his communications with a person identified only as "Person A" in court documents.

Authorities also accused Van Der Zwaan of failing to produce emails between himself and the unidentified person.

He pleaded guilty Tuesday afternoon, according to The Associated Press.

Van Der Zwaan worked as an associate in the London office of Skadden, Arps, Slate, Meagher & Flom, according to a LinkedIn page that has since been taken down and Bloomberg News.

The New York Times reported in September that Justice Department officials were seeking information from Skadden, a prominent New York law firm, in connection to its work for Ukraine. Manafort used Skadden to help shield one of his clients, former Ukrainian President Viktor Yanukovych, from criticism over his prosecution of Tymoshenko, according to the newspaper.

Tymoshenko was convicted of abusing her office in 2011 in a case that drew condemnation from the European Union, Reuters reported. Critics accused Yanukovych of pursuing charges against Tymoshenko for political reasons.